1. Field of the Invention
The present general inventive concept relates to a power line communication (PLC) method and apparatus, and more particularly, to transmission of data packets using a repeater in a PLC method and apparatus.
2. Description of the Related Art
Power line communication (PLC) is a type of communication in which data is transmitted over power lines. In PLC, a data signal is carried on a 60 Hz sine wave of a common alternating current (AC) power supply for communication. Thus, all power supply lines in homes or offices serve as communication lines, and thus a communication network can be established without a need to install separate communication lines.
Since it is conventionally understood that a communication distance allowed by PLC technology is more than 100 m, problems with PLC do not occur in most homes in theory. However, in practice, there may be an electrical outlet in a position having a poor communication state due to a wiring structure on the premises or load generated in a cabinet panel. In this case, a repeater function used in an access network may be a solution for this problem. However, when a repeater is simply used, a specific communication device should communicate via the repeater all the time, and thus communication devices, though being capable of efficiently communicating with each other without using the repeater, are likely to perform communication via the repeater. In this case, by using the repeater, communication efficiency is degraded. Therefore, there is a need for a technique capable of selectively repeating communication between communication devices having link qualities that are lower than a threshold level.
Even when a repeater is used, a user's direct setting is required, resulting in low efficiency. In other words, the user should directly check non-communication between two stations and directly set the repeater between the stations. Moreover, since different group IDs (GIDs) should be set, the repeater cannot be used within the same group.